1. Field of the Invention
The present invention relates to a method for processing information on chemical reactions and more particularly, to a method for processing information on changes in the chemical structures of substances concerned with chemical reactions.
2. Description of the Prior Art
Various methods for recording structural information on chemical substances, particularly organic compounds have been proposed and attempted with the development of computers in recent years. A vast amount of organic compounds and organic reactions have been studied and worked out up to the present, and it is highly required that known chemical substances or chemical reactions are retrieved in a short time, or methods for the synthesis of new substances having the desired properties are found out, by effectively utilizing information on said known compounds and reactions. For this purpose, development of a new representation mode for chemical substances and chemical reactions is needed, which can be processed by computer (that is, which can be logically judged by computer) instead of an ordinary mode such as structural formula which can be readily treated by chemists.
Typical methods for recording chemical substances (methods for the representation or description of chemical substances) are a linear notation method such as WLN (Wiswesser Linear Notation) and a method using connection table. These methods are described in, for example, W. T. Wipke, S. R. Heller, R. J. Feldmann and E. Hyde (Eds.): "Computer Representation and Manipulation of Chemical Information", John Wiley and Sons, New York, 1974. The connection table is a list in which the kind of atoms and the kinds of neighbor atoms and bonds, etc. appeared in the structural formula of chemical substance are tabulated and the connection table has an advantage that chemical substances can be retrieved atom by atom as compared with the linear notation.
Further, methods for recording information on change in the chemical structures of substances (on chemical reactions) have been proposed, but a satisfactory representation method is not developed as yet. For instance, as methods for the description of chemical reactions, there are methods using a reaction code, such as a method described in J. Valls and O. Scheiner: "Chemical Information Systems", ed. by E. Ash and E. Hyde, Ellis Horwood Limited, 1975, p. 231-248; a method described in M. A. Lobeck, Angew. Chem. Intern. Ed. Engl., 9, 578(1970); and a method described in H. J. Ziegler, J. Chem. Inf. Comput. Sci., 19, 141(1979). In these methods, a view of the representation for chemical reactions is fixed and hence, these methods have a disadvantage that any novel chemical reactions can not be described. Further, there are disadvantages that since structural information on chemical substances and information on structural changes thereof are recorded in a separate form, it is hard to make an effective information retrieval.
There are other known recording methods worked out for design of synthetic pathways of chemical substances, for instance, methods described in E. J. Corey, R. D. Cramer and W. J. Howe, J. Am. Chem. Soc., 94, 440(1972); and I. Ugi, J. Bauer, J. Braodt, J. Friedrich, J. Gasteiger, L. Jochum and W. Schubert, Angew. Chem. Intern. Ed. Engl., 18, 111(1979).